The present invention relates to devices for warning a person moving along a given path against the presence on the path of objects that might present a danger for that person, and more particularly, but not exclusively, it relates to devices for providing individual protection against objects such as explosive mines or the like.
Devices are already known for detecting and locating objects which are hidden from human view by other materials, for example by being buried in the ground, in sand, etc.
Some of those known devices operate by detecting metals used in making such objects, e.g. making use of the ability of metals to reflect certain electromagnetic waves.
For that purpose, those devices essentially comprise two antennas, a transmitting antenna for transmitting electromagnetic waves and a receiving antenna suitable for picking up waves reflected on the reflecting portions of buried objects. By analyzing the signal delivered at the output from the receiving antenna, it is possible to determine whether or not an object is present, for example a mine that might be dangerous.
Naturally, there exist other types of detectors for detecting objects buried in the ground or in any other material, and operating on the basis of physical properties of said objects other than the ability to reflect electromagnetic waves. Thus, there exist detectors based on receiving magnetic radiation, visible or invisible light waves, sound waves, chemical reactions, etc.
All those object-detection devices are well known in themselves and are not described in greater detail herein, particularly since they are readily available in the trade and anyone can easily get hold of one.
It is also recalled that devices are known which enable specialists, such as mine-clearance experts, etc., to detect the presence of possibly dangerous objects, e.g. explosive mines, on a given path, which objects could prevent people from moving along the path in safety.
In outline, those devices comprise an object detector placed at one end of a pole, the other end of the pole having means enabling the expert to hold it and move the object detector out in front in order to look for and locate any such objects. It is therefore quite clear that those devices prevent the people that use them from performing any function other than locating mines or the like.
In particular, they cannot reasonably be used by people needing to move along a given path where the ground is likely to contain mines or the like, but who are supposed to be performing functions other than mine clearance, for example as combatants or the like. Under such circumstances, they cannot simultaneously carry and hold both an object-detection device as described above, and also their normal combat equipment, guns, or the like.
It is true that combatants are generally called on to advance along paths from which specialist services have already cleared the mines. However, there is always the risk of some mines being overlooked, and in particular numerous operations need to be capable of being carried out as quickly as possible, before it has been possible to clear the mines from a path that is to be taken by such combatants or the like.
Devices have therefore been developed that make it possible to warn such people when a suspect object has been detected so that they can avoid going any further forwards. Such devices are described, for example, in GB-A-2 123 559 and in DE-A-30 27 189. Those devices essentially comprise an alarm constituted by a vibrator, for example, which is pressed against the skin of the person. With such a device, the person must begin by perceiving the signal delivered by the alarm, must then understand it, and must finally take the appropriate mental action to stop and withdraw a leg, e.g. by pulling it back. The time required for those four operations to be performed, corresponding to a stimulation reflex, is about one hundred milliseconds.
An object of the present invention is to provide a device making it possible to warn a person moving along a given path against the presence on the path of an object that might be dangerous for that person, and a device which serves, in particular, to relieve that person of the constraints associated with manual use of prior art object detector devices, while still providing good safety to a person advancing along the path, and above all, enabling that person to stop advancing along the path much more quickly than is possible with prior art devices of the kind outlined above.
More precisely, the present invention provides a device for warning a person moving along a given path against the presence on the path of objects that might be dangerous for that person, the device comprising:
detection means for detecting said objects, said detection means being suitable for delivering a detection signal on an output, a change of state in said signal being indicative of the presence of said object in a predetermined zone of said path; and
means for connecting the object detection means to a first portion of the body of said person;
the device being characterized by the fact that it further comprises means for converting said detection signal into an electrical function-stimulating signal acting on a second portion of the body of said person.